Backpacks May Not Cause Kids' Back Pain

May 21, 2003 -- Heavy, book-crammed backpacks are often blamed for back pain in children, but a new study suggests that their soreness and strain may result from a different load being carried -- their own weight.

Research presented Wednesday at the International Society of Physical and Rehabilitation Medicine in Prague suggests there is no link between backpacks and back pain in children. Rather, researchers say that lack of physical activity and children's own girth are a more likely cause.

The researchers weighed 184 third graders and middle school students, along with their typical backpack loads, and asked them about back pain. Researchers found that back pain in children was not higher among those who carried heavier backpacks or carried them on one shoulder. But they did find that the older kids were three times more likely to report back pain than the third graders -- and were also more likely to be fatter and less active. Overall, one in three children had back pain.

"As kids got older, they watched more TV and video games, walked or rode a bike to school less often, and had higher body mass indexes," says lead researcher and physiatrist Andrew Haig, MD, medical director of the University of Michigan Spine Program, who presented to study. "Obesity and deconditioning are tempting culprits, so we should concentrate on them."

Haig says that most American children don't usually carry backpacks long enough to trigger back pain. "Their use is typically an up-and-down thing -- carry it to the bus stop, put it down, carry it on the bus, put it down, carry it to class, put it down while talking to a friend," he tells WebMD. "We did have a range of weights carried, including some up to about 30% of their body weight. Given our results, I think it's incumbent on people who still believe there is a problem with heavier weights to both prove this and to show the relevance to American kids."

Still, in his study the average backpack load was only about 6% of total body weight among the third graders and 11% among middle schoolers. And that may explain why no link was found between backpacks and back pain in the children, says one expert.